A developing device includes: a developer carrying member; a developer container including a developer accommodating portion, a developing opening and a developing chamber; and a developer supplying member including a shaft member and a feeding member. The feeding member includes a first feeding portion having a length L1 and a radius R1, and includes a second feeding portion having a length L2 and a radius R2. When a length of the developing opening is L3, a shortest length from the developing opening to the rotation center of the shaft member is L4, and a length from the developer carrying member to the rotation center of the shaft member is L5, the following relationships are satisfied: L1